Solvent of acetyl cellulose.



UNITED STATES PATENT OFFICE.

WILLIAM G. LINDSAY, OE CALDWELL, NEW JERSEY, ASSIGNOR TO THE CELLULOID COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

SOLVENT OF ACETYL CELLULOSE.

No Drawing.

To all whom it may concern:

Be it known that I, WILLIAM G. LINDSAY, a citizen of the United States, residing in Caldwell, county of Essex, State of New Jersey, have invented certain new and use ful Improvements in Solvents of Acetyl Cellulose, of which the following is a specilication.

The various compositions to which the present invention relates are employed in the arts, sometimes as imitations of natural substances and sometimes as films which are used for photographic purposes.

Although the final or useful form of the different compounds of acetyl cellulose is that of a solid or dry material, the different processes of conversion into this final solid form involve, as is well understood, the employmentof solutions or mixtures of varying consistency as to plasticity, stiffness or fluidity, dependent generally upon the proportion and kind of solvent used to the amount of the original base-acetyl cellulose.

In the treatment of acetyl cellulose for the production of plastic masses which can be utilized in a manner similar to the nitro cellulose compounds, the best known of which has received the trade name of celluloid, and the production of solutions for the manufacture of lacquers, varnishes, ho tographic films and flexible compoun s, I have discovered that methyl acetate in admixture with methyl alcohol exerts a solvent action on that variety of cellulose which is freely soluble in acetone.

It is well known that methyl acetate has been proposed as a solvent for the acetonesoluble variety of acetyl cellulose, and that the methyl acetate found on the market contains varying amounts of methyl alcohol. I have discovered, however, that when the commercial or the 100 per cent. methyl acetate is diluted with methyl alcohol in certain proportions there results a product of increased solvent action for the preparation of acetyl cellulose compounds. The best proportions I have found are 30 per cent. to 40 per cent. of methyl alcohol and 60 per cent. to per cent. of methyl acetate. This constitutes the liquid solvent mixture, although the proportions may be varied without departure from the spirit of my inveution.

An example of carrying out my process which, in addition to the new solvents, 00n- Speciflcation of Letters Patent.

Patented June 27, 1916.

' Application filed May 23, 1912. Serial No. 699,236.

stitutes the subject of my discovery is as follows: To 100 parts, by weight, of the acetone-soluble variety of acetyl cellulose I add from 10 to 20 parts of paraethyltoluolsulfonamid and incorporate these substances. I then add from 60 to 70 parts, by weight, of a mixture composed of 70 parts by volume of methyl acetate and 30 parts by volume of methyl alcohol. The mixture is then thoroughly incorporated by malaxatmg and when a uniform mixture is obtained the excess of solvent is allowed to evaporate and the dough-like mass thus obtained is further worked up according to the method which is well known in the manufacture of nitro-cellulose-camphor compounds.

Again, in order to make a compound which is plastic but which is not inflammable, I proceed as follows: To 100 parts by weight of the acetone-soluble variety of acetyl cellulose I add 10 to 20 parts of paraethyltoluolsulfonamid and 20 to 30 parts of triphenylphosphate; to the mixture thus obtained I add from 60 to 70 parts by weight of a mixture composed of 70 parts by volume of methyl acetate and 30 parts by volume of methyl alcohol. The mixture is then incorporated by suitable malaxating or kneading, etc., and when a uniform consistency is obtained the excess of solvent is allowed to evaporate, and the dou h-like mass thus produced is further works up according to the method which is well known in the manufacture of nitro-cellulose-eamphor compounds.

Having thus described my invention what I claim 1s:

1. The solvent for acetyl cellulose that is freely soluble in acetone, comprising about 60-70 parts by volume of methyl acetate and 3040 parts of methyl alcohol, substantially as described.

2. The composition of matter comprising acetyl cellulose which is freely soluble in acetone, about 60-70 parts by volume of methyl acetate and 30-40 parts of methyl alcohol, substantially in the proportions specified, and further comprising paraethyltoluolsulfonamid.

3. The composition of matter comprising acetyl cellulose which is freely soluble in acetone, about 6070 parts by volume of methyl acetate and 3M0 arts of methyl alcohol, and further comprising paraethyltoluolsulfonamid and triphenylphosphate.

4. The composition of matter which comparaethyltoluolsulfonamid and triphenylprises acetyl cellulose which is freely soluble phosphate. in acetone, methyl acetate, methyl alcohol and paraethyltoluolsulfonamid.

5. The composition of matter which com- Witnesses: prises acetyl cellulose which is freely soluble RUTH MEYERsoN, in acetone, methyl acetate, methyl alcohol, J. E. MINDONTHYDEL.

\VILLIAM G. LINDSAY.

v 4 The composition of matter which .com-

prises acetyl cellulose which is 'freely soluble phosphate. in acetone, methyl acetate,v methyl alcohol VILLIAM G. LINDSAY. and par21ethyltoluolsulfonamld. W

5. The composition of matter which com- 1 ltIlESSQS'I prises acetyl cellulose which is freely soluble in acetone, methyl acetate, methyl alcohol,

RUTH MEYERsoN, J. E. MIXDONTHYDEL.

It "s hereby certified that in Letters Patent No. 1,188,799, granted June 27,

1916, upon the application of William G. Lindsay, of Caldwell, New Jersey, for an improvement in Solvents of Acetyl Cellulose, errors appear in the printed specification requiring correction as follows: Page '1, lines 1 02-103, claim 2, strike out the words substantially in the proportions speciiied; page 2, lines 2 and 6,

claims 4 and 5, before the Word acetyl insert the words that variety of; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 22d day of August, A. D., 1916.

' [SEAL] s p F. W. H. CLAY,

Acting Commissioner of Patents.

paraethyltoluolsulfonamid and triphenyh It 's hereby certified that in Letters Patent No. 1,188,799, granted June 27, 1916, upon the application of William G. Lindsay, of Caldwell, New Jersey, for an improvement in Solvents of Acetyl Cellulose," errors appear in the printed specification requiring correction as follows: Page 1, lines l02l03, claim 2, strike out the words substantially in the proportions specified; page 2, lines 2 and 6, claims 4 and 5, before the word "acetyl insert the words that variety Qf, and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 22d day of August, A. D., 1916.

[SEAL] F. w. H. CLAY,

Ad'i'ng Commissioner of Patents. Cl. 106-40. 

